diff --git a/src/os_win32.h b/src/os_win32.h
index a98951e..3cc0f47 100644
--- a/src/os_win32.h
+++ b/src/os_win32.h
@@ -198,7 +198,7 @@
 
   // These macros should all compile away to nothing
 # define ASSERT(f)		((void)0)
-# define TRACE			1 ? (void)0 : printf
+# define TRACE			1 ? (void)0 : (void)printf
 # define TRACE0(sz)
 # define TRACE1(sz, p1)
 # define TRACE2(sz, p1, p2)